Astronomers created a remarkable map showing 25,000 supermassive black holes, detected not by light, but by the powerful radio waves emitted from their relativistic jets. The map was made possible using a network of 52 radio telescopes across Europe, known as LOFAR, which captured low-frequency radio signals from distant galaxies in the northern sky. Earth’s ionosphere distorts low-frequency radio waves, so researchers developed a supercomputer algorithm that corrected these distortions every four seconds during 256 hours of observation. The current map covers just 4% of the northern sky, but the astronomers aim to create a full atlas of supermassive black holes across the entire hemisphere. This study is another example of how advanced computer algorithms, like those used to capture the first black hole image in 2019, are revolutionizing our ability to observe the universe.
Mapping the Unseen Universe
How would life be if you saw what is not shown? Now, a group of astronomers have done just that. They explain how they have mapped 25,000 supermassive black holes in our northern sky.
The feat was accomplished with the help of the front-line Low-Frequency Array (LOFAR), a set of 52 radio telescopes across Europe, forming a diamond-shaped network. Between them, they have brought our knowledge of black holes into near-science-fictional territory.
John Mirt Bexti Franciscode Gasperin from Universität Hamburg, said that Francesco de Gasperin was the lead from his institution on this project. "This is the product of years and long hours working with some very challenging data," he said. Amazing how brilliant minds can figure out cosmic mysteries, right?
A black hole is shown at the center of each point on this map, and there are many other far-off galaxies showing us just how huge our cosmic home really is. But black holes are more than just empty spaces; they are being illuminated as they gorge on gas and dust from the surrounding area.
Picture a black hole swallowing up a far-off star. The star kind of falls in and forms an accretion disk. The material can whirl at close to the speed of light and create magnetic fields so powerful they might shoot jets of particles across space.
Our telescopes can pick up the radio waves these jets give off. All at once, you could see the dark.
A Technological Marvel
How did they then magically transform cosmic giants into these beautiful images? It is with the innovative algorithms. The team collected data during more than 256 hours while their supercomputer corrected ionospheric distortions every four seconds.
It's quite an amazing thing to imagine that they took chaos and turned it into clarity by giving us such dynamic visuals of black holes hiding in the voids out there. Observational astronomy is challenged by the presence of an ionosphere. Anything above 30 MHz is puzzling as it's like looking at the world while underwater, said study co-author Reinout van Weeren.
Wave distortion is a challenge, or it could be seen as an aspect of complex nature. The way we adapt to these challenges shows human ingenuity. But this amazing journey is not limited to just black holes; this mirrors our increasing dependence on algorithms in science.
The same year, a team led by Katie Bouman adopted something similar to create the first-ever picture of a black hole. Look at how far we've come! Leiden Observatory contributor Huub Röttgering was also pleased to hit this benchmark.
For long-time software developer Folsy, at least some of the appeal arises because “it feels great to have this finally pulled off after so many years in development.” You have to admit, this is some very inspiring stuff — a game development renaissance powered by years of grinding until cracks in the stone started appearing.
Foreglimpses of Our Cosmic Future
Published in Astronomy & Astrophysics, the map only really scratches the surface. How exciting to ponder what more might be out there amongst the stars?! This project has the potential to find many more mysterious black holes hidden in the northern skies.
As the algorithms improve, so does our ability to navigate beyond this world. For instance, think of peering farther into the universe than anyone has ever imagined. There is no end to the secrets it could potentially help uncover.
The excitement of the research is tangible, but here, any new discovery opens more doors than it closes. What further revelations in these cosmic phenomena can we pursue? But this study is only the start.
As technology advances, so do our dreams to map the universe. More amazing cosmic objects that were previously out of reach may be accessible once the full sky can point to where they are. Are you prepared for what they will uncover this time?
Yet it is still a massive, unknown canvas of the cosmos with all its darkness and light interwoven. Because as we dive down this rabbit hole, maybe we can also peek and see some black holes together with our faces in the cosmic corridor spirit?
